Battery cells for Battery Electric Vehicles (BEV), Hybrid Electric Vehicles (HEV) and Partial Hybrid Electric Vehicles (PHEV) are remotely packaged away from anticipated crash zones to reduce the risk of damage as a result of a collision. The central area under the passenger compartment floor is a potential location for the battery because it is spaced away from the outer body of the vehicle and is protected by sub-floor cross car members, rocker assemblies, and underbody side frame structures. Under floor packaging is relatively a safe zone for the battery pack in full frontal and rear barrier crashes. However, in side crashes such as Moving Deformable Barrier (MDB) test and Side Pole (SP) test, vehicle rockers and cross members have a tendency to bend and wrap around the impacting barrier or pole. The most severe damage to battery compartment occurs during side pole impacts. Side body impacts may cause the floor structure to collapse towards the battery pack and may increase the risk of damage to the battery system.
To avoid damage to the battery pack, one approach was tested in a simulation in which a gap of about 8 inches was provided on both sides of the floor along with up-gaging and strengthening the rocker and cross-members with additional reinforcements, and higher strength materials. Limiting side pole intrusions to less than 8″ into the floor structure can be achieved with sufficient strengthening of the rocker and cross-members thereby avoiding potential damage to battery pack. However, strengthening the body structure results in much higher cost and weight penalty, and reduces the benefits to be gained from having a BEV, HEV or PHEV in terms of energy efficiency and exhaust emissions.
This disclosure is directed to solving the above problems and other problems as summarized below.